题目内容
(1)-3
÷(-1
)×(-4
);
(2)(-27
)÷9-(
+
-
-
)×(-24).
| 4 |
| 7 |
| 2 |
| 3 |
| 2 |
| 3 |
(2)(-27
| 9 |
| 11 |
| 1 |
| 2 |
| 2 |
| 3 |
| 3 |
| 4 |
| 11 |
| 12 |
分析:(1)先把带分数变成假分数,同时把除法变成乘法,再按有理数的乘法计算即可;
(2)把除法变成乘法,再按乘法分配律展开,最后先计算乘法、再计算加减.
(2)把除法变成乘法,再按乘法分配律展开,最后先计算乘法、再计算加减.
解答:解:(1)原式=-
×(-
)×(-
)
=-10;
(2)原式=(-27-
)×
+(
+
-
-
)×24
=-27×
-
×
+
×24+
×24-
×24-
×24
=-3-
+12+16-18-22
=-15
.
| 25 |
| 7 |
| 3 |
| 5 |
| 14 |
| 3 |
=-10;
(2)原式=(-27-
| 9 |
| 11 |
| 1 |
| 9 |
| 1 |
| 2 |
| 2 |
| 3 |
| 3 |
| 4 |
| 11 |
| 12 |
=-27×
| 1 |
| 9 |
| 9 |
| 11 |
| 1 |
| 9 |
| 1 |
| 2 |
| 2 |
| 3 |
| 3 |
| 4 |
| 11 |
| 12 |
=-3-
| 1 |
| 11 |
=-15
| 1 |
| 11 |
点评:本题考查了有理数的混合运算,注意:①运算顺序,②乘法分配律的灵活运用.
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